Vacuum-pump



(No Model.)

W; E. NICKERSON & A. BERRENBERG. VACUUM PUMP.

No. 452,441. Patented May 19,1891.

Fig.1.

I? L 2 5 1 I 1 7e 0 R 1 1 r z o 1 O J T T A 7? 1 O O Q 55 O O O O WITE5555 Fi .2. INVENTD 5 UNITED STATES PATENT OFFICE.

ADOLPH BEBRENBERG, OF TO THE BEACON VACUUM PUMP AND ELECTRICAL COMPANY,OF PORTLAND, MAINE.

VACU UM-PUMP.

SPECIFICATION forming part of Letters Patent No. 452,441, dated May 19,1891. Application filed June 2, 1890. $erial No. 354,035. (No model.)

To all whom it may concern,-

Beit known that we, WILLIAM E. NICKER- SON, of Cambridge, and ADOLPHBERREN- BERG, of Somerville, both in the county of Middlesex and Stateof Massachusetts, have invented certain new and useful Improvements inVacuum-Pumps, of which the following, taken in connection with theaccompanying drawings, is a specification. to This invention relates tothe construction,

arrangement, sealing, and methodof coworking the cylinders of avacuum-pump.

The object is to simplify the mechanism and to secure superior results.This object I we attain by the devices shown in the accompanyingdrawings, in which Figure 1 is a View in which some of the parts areshown in vertical section and some in elevation. Fig. 2 is a plan of thedevice with the top removed.

In the drawings,A represents atank made large enough to hold one or morepump'cylinders and their connections. This tank is to be filled with oilor other suitable fluid,

and it it is large it must be properly braced and stayed. Near thebottom of this tank a crank-shaft H is hung on suitable housings andbearings, as shown. The shaft H passes out of the tank through thestuffing-box H then through the oil S in the pocket H to a secondstuffing-box H and has driving-gears; (Not shown.)

lVithin the oil-tank four cylinders B C D E are shown, supported,respectively, upon 35. base-pieces B C D E. These cylinders aresubstantially alike and a description of one E will do for all. Thecylinder proper E,

coned at the top, as shown, is supported on a base E and has a piston Ealso coned, connected by a pitnian E to its crank on the crank-shaft H.At the top of the cylinderE a downwardly-closing valve E is placed. A

port (indicated by dotted lines at E) is made in the side of thecylinder.

As has alreadybeen stated, the cylinders B, C, D, and E and theirpistons, valves, and ports are alike, and therefore require no furtherdescription except to refer to the connections with the inlet and outletpipes and to their coworking.

The system of pipes and valve connections will now be described. P is apipe leading from the article to be exhausted. This pipe is connected tothe interior of cylinder B by a branch P, Fig. 2, which terminates inthe port B, (see Fig. 1,) and to the interior of the cylinder C by abeudP Fig. '2, which terminates in the port C Fig. 1. The pipe R isconnected to the valves in the tops of the cylinders B and C, (theirvalves being in all respects like the valve E, shown in section in Fig.1,) thence the pipe Rturns downward and rearward, as shown, and isconnected to the ports D and in the cylinders D and E. The pipe R isconnected by a pipe to an air-dome A. (See Fig. l.) The pipe T connectsat T with the valve D in the top of the cylinder D and at T with thevalve E in the top of the cylinder E, thence the pipe T passes out ofthe tank and terminates at T over a return-box H, which is connected tothe tank, as shown, having a downwardlyclosing valve h, attached to afloat H The top of the entire tank A maybe covered with oil, asindicated.

The operation of this pump is as follows: The tank is nearly filled withoil or other suitable fluid, that is-a sui'iicient quantity is put in itto cover all of the parts, but leaving a space above, as shown. The topmay be covered with oil for the purpose of sealing the joints. Now asthe crank-shaft H rotates, the pistons in the cylinders B and D descendand those in C and E ascend.

The pumping action is as follows: Suppos- 8 5 in g that a half-turn ofthe crank-shaftis made, a vacuum is formed in the cylinder B, while airis forced out of cylinder C through the pipe R R, and to the dome A avacuum is formed in cylinder D, and air is forced out of cylinder Ethrough the pipe T to the open air. At the completion of the half-turnof the crank-shaft the ports B and D in the exhausted cylinders B and Dwill be open and air will flow to B throughthe pipe P from the articlebeing exhausted, and air will flow into the cylinder D through the pipeR from the cylinder B and the, articles being exhausted, and through thepipes R and the lower part of the pipe R from the dome A and the upperpart of the tankthat is, from the part of the tank not occupied by theoil. In this action the pump performs another important function,namely:It by exhaustingfrom above the oil in the tank causes the deaeration ofthe oil in the said tank and renders it a suitable fluid for filling thespaces around the pumpcylindersandtheireonnectionsforthepurpose ofpreventing any air or other vapor from entering the vacuum-spaces withinthe cylinders and their connections. Now supposing the crank-shaft tomake another half-turn, the ports 13 in cylinder B and D in cylinder Dwill be closed, and the inclosed air will be forced out, the air from Bgoing to the dome A and from D through the pipe T to theopen air. WVhilethis is going on the cylinders O and E are exhausting, 0 through pipe Ifrom the article being exhausted and the cylinder E through the pipe R Rfrom the dome A. This comprises the work done by a full turn of thecrank-shaft, and repetition of the rotation simply repeats the pumpingaction of all the cylinders. As the work goes on,the vacuum in thearticle being exhausted and in the dome and in the space above the oilin the tank is improved until the desired minimum of air tension isattained. All of the cylinders are supplied with a small quantity of oilat each stroke of the pistons, the oil passing through small ports madein the sides of the cylinders for that purpose, one of which ports isshown at E Fig. 1. These oil-ports are covered and uncovered by thepiston itself the same asare the airports B C D and The excess of oil isforced out together with the air at each upward stroke of the piston.The oil thus admitted serves to completely expel the air from thecylinders at each upward stroke of the piston. This oil flows fromcylinders B and 0 through the pipe R R to the cylinders I) and E, andthence through the pipe T to the box H", whence its flow back into thetank A is regulated by the float H and valve h.

In the above description of the working of this pump it is seen that theseveral pistons and cylinders cowork to produce the result. Thus thepiston D produces a vacuum for the cylinder B to discharge into, whilethe piston E produces a vacuum for the cylinder C to discharge into. Bythis coworking of the individual pumps very rapid and efficient work isaccomplished.

The above-described arrangement, except as to coworking, may be modifiedso as to apply to a single cylinder. For instance, take the cylinder Eand let the exhaust-pipe R" run directly to the article to beexhaustedsay lamps'and have the delivery-pipe T T unconnected with anyother pump and pass directly to the oil-box 11. Now this single cylinderwould become for most purposes a very efficient pump.

e claim- 1. An air-tight tank containing a sufficiency of oil to whollysubmerge an inclosed pumpcylinder, wit-h a pump-cylinder the interior ofwhich is connected to the articles to be exhausted, and also to anair-space in the tank and above the oil, whereby the action of the pumpwill exhaust the air from the articles to be exhausted, and also fromthe tank and from the oil inclosed within the tank, said cylinder havinga port for admitting above the piston a small portion of oil for thepurpose of expelling all the air from the cylinder at each upward strokeof the piston, a piston the length of which exceeds the length of itsstroke, whereby the port for the admission of air is open only duringthe lower portion of the stroke of the piston, and a valved outletportat the top of the cylinder, substantially as and for the purpose setforth.

2. In a vacuum device, the combination of one or more vacuum-pumps andan inclosirg tank, said tank being exhausted of air and containingsufficient oil to wholly submerge the said pumps, with a return-box H,located at the top of .said tank, having a valved connection therewithand adapted to receive and return to the tank the surplus ofair-expelling oil forced from the pumpat each upward stroke of thepiston, substantially as and for the purpose set forth.

WILLIAM E. NIOKERSON. ADOLPH BERRENBERG. Witnesses:

FRANK G. PARKER, WILLIAM EDSON.

